Some storage systems may store digital information in tape-based storage media (hereinafter, “tape”), such as magnetic tape. A tape storage drive is an electronic device that can read data from and write data to tape. A tape cartridge may house a reel of tape, and the tape cartridge may be loaded into a tape storage drive to make the tape available for reading/writing. A tape cartridge may also include a cartridge memory, which is a data storage device that may store information about the tape cartridge, such as manufacturer identifiers, a specification of the format of the tape cartridge, and other configuration and/or initialization information.
The formats of tape cartridges and the tape drives that utilize them may be specified in an format specification (such as one of the Linear Tape-Open (“LTO”) generations) or a proprietary specification (such as in IBM's 3592 series). Such open formats and proprietary specifications (both will be referred to hereinafter as simply “specifications”) may specify, among other things, the form factors of the tape cartridge and the tape, a configuration of the tape drives, and a format for data storage on the tape (hereinafter “tape format”). In particular, the tape format may include, for example, a total storage capacity for a cartridge, how stored bits are to be organized on the tape (e.g., bands, wraps, tracks, etc.), whether/how bits are to be encrypted and/or compressed, and so on. For example, LTO6 compliant tape cartridges may use one tape format that has 2.5 TB capacity, while LTO7 compliant tape cartridges may use another tape format that has 6 TB capacity (note that the number following “LTO” designates a generation).
In some examples, a single tape cartridge may be compatible with (i.e., capable of using) multiple tape formats. Such cartridges may be referred to herein as multiple-format cartridges. For example, if two different tape specifications have the same cartridge and tape form factors as one another, but have different tape formats, then in some instances a single tape cartridge might be capable of being formatted according to either of the two specifications. For example, a given tape cartridge may be capable of being formatted according to LTO7, but it also may also be capable of being formatted according to LTO7-Type M (although not both at the same time). As another example, an IBM JC tape cartridge may be capable of being formatted according to either of IBM's TS1150 or TS1140 formats.